Above normal risk of floods in northern Illinois

ROCKFORD - There is an above-normal risk for flooding this spring, according the National Weather Service's branch office in Romeoville.

The office was one of several Midwestern branch offices to release its 2014 spring flood outlook report late Thursday.

Because of the extensive ice cover on area rivers, ice jams and ice jam flooding pose a "significant threat" this spring, the report said. Ice jams can result in rapid rises in water levels in a short time. The amount of rainfall or additional snow and subsequent snowmelt in the coming weeks will determine the severity of any future flooding.

The spring outlook is based on hydrologic conditions such as current soil moisture, snowpack and streamflow conditions at the time of issuance.

The National Weather Service said the risk of flooding further south into Midwest is not as great.

The Rock Island weather service office projects near-normal flood risk on the Mississippi River in most of Iowa and Illinois, but a slightly elevated risk from Dubuque, Iowa, south to the far northeastern Missouri.

That's a bit of a surprise considering how snowy the winter has been. Parts of Minnesota, Wisconsin and Iowa still have up to 3 feet of snow on the ground.

The snowfall has been offset by unusually low river levels and drought, said National Weather Service hydrologist Mark Fuchs in suburban St. Louis. He said that when the snow melts, much of it is expected to go into the parched ground.

"There is a fair amount of snow up north but there is also a drought up north," Fuchs said Friday. "That's the one thing that's going to mitigate the flood potential."

Long-term rainfall projections call for around average precipitation in the spring. Fuchs said if that's accurate, minor flooding could be expected in parts of the Mississippi River from southern Iowa to the Missouri River confluence near St. Louis. Mississippi River tributaries could also see mostly minor flooding.

Some rivers in Missouri, Illinois and Indiana are already out of their banks, though the flooding is expected to be minor and brief.

This week's unusually warm temperatures caused significant snow melt in northern Missouri. Combined with up to an inch of rain in the middle of the week, a few rivers spilled over their banks. Ewing, a tiny community about 120 miles north of St. Louis, was hardest hit, but damage was mostly limited to farmland and county roads.

Spring flood predictions for the region south of St. Louis are difficult to project because the National Weather Service hasn't yet developing flood modeling for the Missouri River, which plays such an important role in Mississippi River depths below the confluence.

The spring outlook from the weather service's Sioux Falls, S.D., office calls for a lower than normal chance of flooding over much of the Dakotas and into Nebraska. The Des Moines, Iowa, office projects near-normal flood risks over most of Iowa, saying that below-normal soil moisture offsets deep frost that often raises flood concern.

Fuchs cautioned that a strong and extended storm or two could wipe out all the hopeful predictions.